by Gary Levin, USA TODAY

by Gary Levin, USA TODAY

Don Draper returned on a downbeat note, and AMC's Mad Men had a slight downturn in Sunday's premiere audience, the first year-to-year decline for the series since it began in 2007.

The sixth-season premiere, which started with a Hawaiian vacation and focused on themes of mortality, averaged 3.4 million same-day viewers, down from 3.5 million for last March's opener. It was up from the full fifth-season average of 2.6 million, as premieres often prove more popular than subsequent episodes.

When all DVR usage is factored in, the total audience could climb slightly higher. But Men, AMC's signature series, repeat Emmy winner and first breakout original, still commands a fraction of the audience of zombie hit The Walking Dead, which had more than 12 million viewers for the first and last episodes of its just-concluded winter season.